In order to measure forces in a biomechanical study, a strain gauge with gauge factor 5 and initial resistance of R0=10k is bonded to one of the bones of a cadaver foot. A bridge circuit (above) is employed to measure the strain. Initially, the variable resistor is adjusted to balance the bridge under zero load conditions. After the bridge is balanced, a force is applied to the foot, and Vo measures to be 0.5V. What is the strain